The present invention relates to novel curable adhesive compounds, and more particularly to adhesive compounds which have an excellent adhesive strength to adherends made of organic or inorganic materials, and which have good heat aging resistance.
In recent years, a number of so-called second generation acrylic adhesives (hereinafter called "SGA") mainly composed of rubber-like polymers of acrylates or methacrylates have been introduced. These types of adhesives are characterized by the fact that there is no longer a need to weigh and mix two components as in the case of epoxy resin adhesives, and that they have high shear bond strength together with high impact resistance due to the content of the rubber component.
However, conventional SGAs have poor adhesive retention strength at high temperatures, heat aging resistance, fatigue resistance and particularly poor peel bond strength. Many problems could be solved by applying the adhesives to parts or portions where such properties are required. In particular, with respect to conventional SGAs and epoxy resin adhesives, it is quite difficult to increase the peel bond strength without any reduction of the shear bond strength.